1. Field of the Invention
The invention relates to a pivot drive for a front side roof rod of a motor vehicle roof or a convertible folding top which is supported with a pivot joint on a rear side roof rod which is pivotally mounted via a rod arrangement on the motor vehicle body. When the roof or folding top is open, it can be lowered. The roof or folding top is opened and closed by a pivot drive.
2. Description of Related Art
Pivoting of the front side roof rods via their own drive when the motor vehicle roof or the convertible folding top is being lowered is known. But control of the drive is necessary for timed swivelling-in of the roof rods.
Published International Patent Application WO 97/37866 discloses a kinematic folding top for a convertible. The top includes a front part of a three-member top frame that is moved out of the closed position by parallel pivoting into a lowered position via a parallelogram rod arrangement. The arrangement connects the side roof rods of the front part to those of the middle part. In the lowered position the front part of the folding top is identically cambered, i.e. with identically pointed arching, on the middle part of the cover. The motion of parallel pivoting of the first part of the folding top is forcibly coupled via a control lever to the lowering motion of the rear part of the folding top.
A primary object of the present invention is to provide a pivot drive which does not have any fault-susceptible control.
This object is achieved with a connector which engagingly couples the front roofrod to a rod arrangement which connects the motor vehicle body to a rear roof rod. The connector pivots relative to the rear roof rod when the roof or folding top is being lowered such that the pivoting motion of the rear roof rod pivots the front roof rod. This rod coupling or joint coupling results in mechanical coupling and transfer of motion which does not require either its own drive or an electronic control, but which proceeds in a restrained manner by the rod arrangement which lowers the roof or folding top into the lowered position. Instead of in a convertible with a fabric folding top, the pivot drive of the present invention can also be used in motor vehicle roofs with solid roof elements to clear a targa-like or convertible-like roof opening.
The pivot drive coordinates a pivoting motion of the front roof rods which takes place in a roughly horizontal plane of the motor vehicle such that the right and the left inwardly pivoting front roof rods do not mutually hinder one another.
The roof or folding top may be supported on the body by pivotally mounting the rear roof rods on the body with a parallelogram-like four-bar arrangement which contains a main column and a main connecting rod. An electrical or hydraulic main drive acts, for example, on the main column and moves the entire four-bar arrangement and, thus, the folding roof.
In one advantageous embodiment, the four-bar arrangement is coupled via a connector to the front roof rod. During the lowering of the folding top into the lowered position, the pivoting of the connector pivots the front rod.
To pivot horizontally in without problems, it is advantageous if the pivoting of the left and right front roof rods are staggered in time by the connector. In this way, the two pivoting roof rods can be pivoted into a transverse position, for example, on or underneath the main bow or the roof cassette from the left and right side of the folding top without mutual hindrance. The pivoting roof rods can, thus, have a greater length which corresponds, for example, roughly to the width of the folding top.
Feasibly, the connector provides a varying drive speed for the front roof rod. Thus, for example, the transmission of the motion of the connector can be designed such that the pivoting speed of the roof rod is adjusted depending on the pivoting speed of the main column and is variable over the pivoting path. Therefore, at the start and at the end of pivoting, a comparatively slow speed for lowering of the roof rods on the roof cassette and for coupling to the front cross member and in between a higher pivoting speed can be set.
Another embodiment calls for the connector to be driven by the pivoting main column of the four-bar arrangement, but also the main connector can be used as the drive.
Because the connector is coupled in driving engagement via a lock to the main column over a defined pivoting path, it is possible to fix the initial pivot position and the end pivot position of the main column to determine the area in which the connector pivots in an active driving connection when the folding top is being folded in or out.
Feasibly, the connector contains a transmission element which is pivotally mounted concentrically relative to the pivot bearing axis of the main column and next to the main column. The main column is a ring which is in a driving connection to the roof rod via a lever arm and via intermediate rods and joints of the connector.
In one simple embodiment, the lock contains a lock pin which is movably supported in the transmission element or ring, for example, axially, i.e., parallel to the bearing axis. The lock pin is pushed into coupling engagement with the main column depending on the pivoting position of the main column relative to the side part of the roof cassette.
For a reliable sequence of motions, the path of motion of the connector, especially of the lever arm of the ring, is limited by stops. In this way, the roof rods cannot be moved in an uncontrolled manner beyond their end positions.
For uniform and space-saving arrangement of the roof rods, which are pivoted in the transverse direction, it is advantageous if the pivot joints of the roof rods are offset against one another in the lengthwise direction of the motor vehicle. The amount of offset corresponding, for example, to roughly the thickness of the roof rods. The pivot joints have a vertical pivot axis and are arranged on the bilateral side parts of the roof cassette. Thus, also longer roof rods can be pivoted into the lowered position in a space-saving manner.
Preferably, the connector contains transmission gearing so that it is possible to match the input drive motion to the output drive motion. If, in doing so, the transmission gearing converts the input drive motion into a varying output drive motion of the front roof rod. Almost any necessary pivot drive motions for the roof rods can be carried out.
These and further objects, features and advantages of the present invention will become apparent from the following description when taken in connection with the accompanying drawings which, for purposes of illustration only, show several embodiments in accordance with the present invention.